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linux/drivers/serial/bfin_5xx.c
Sonic Zhang 1a3a4c7130 Blackfin Serial Driver: Fix bug - kernel hangs when accessing uart 0 on bf537 when booting u-boot and linux on uart 1 
Wait only when this UART is enabled.
http://blackfin.uclinux.org/gf/project/uclinux-dist/tracker/?action=TrackerItemEdit&tracker_item_id=3995

Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
2008-04-23 09:43:20 +08:00

1328 lines
32 KiB
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/*
* Blackfin On-Chip Serial Driver
*
* Copyright 2006-2007 Analog Devices Inc.
*
* Enter bugs at http://blackfin.uclinux.org/
*
* Licensed under the GPL-2 or later.
*/
#if defined(CONFIG_SERIAL_BFIN_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
#define SUPPORT_SYSRQ
#endif
#include <linux/module.h>
#include <linux/ioport.h>
#include <linux/init.h>
#include <linux/console.h>
#include <linux/sysrq.h>
#include <linux/platform_device.h>
#include <linux/tty.h>
#include <linux/tty_flip.h>
#include <linux/serial_core.h>
#ifdef CONFIG_KGDB_UART
#include <linux/kgdb.h>
#include <asm/irq_regs.h>
#endif
#include <asm/gpio.h>
#include <asm/mach/bfin_serial_5xx.h>
#ifdef CONFIG_SERIAL_BFIN_DMA
#include <linux/dma-mapping.h>
#include <asm/io.h>
#include <asm/irq.h>
#include <asm/cacheflush.h>
#endif
/* UART name and device definitions */
#define BFIN_SERIAL_NAME "ttyBF"
#define BFIN_SERIAL_MAJOR 204
#define BFIN_SERIAL_MINOR 64
/*
* Setup for console. Argument comes from the menuconfig
*/
#define DMA_RX_XCOUNT 512
#define DMA_RX_YCOUNT (PAGE_SIZE / DMA_RX_XCOUNT)
#define DMA_RX_FLUSH_JIFFIES (HZ / 50)
#ifdef CONFIG_SERIAL_BFIN_DMA
static void bfin_serial_dma_tx_chars(struct bfin_serial_port *uart);
#else
static void bfin_serial_tx_chars(struct bfin_serial_port *uart);
#endif
static void bfin_serial_mctrl_check(struct bfin_serial_port *uart);
/*
* interrupts are disabled on entry
*/
static void bfin_serial_stop_tx(struct uart_port *port)
{
struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
struct circ_buf *xmit = &uart->port.info->xmit;
#if !defined(CONFIG_BF54x) && !defined(CONFIG_SERIAL_BFIN_DMA)
unsigned short ier;
#endif
while (!(UART_GET_LSR(uart) & TEMT))
cpu_relax();
#ifdef CONFIG_SERIAL_BFIN_DMA
disable_dma(uart->tx_dma_channel);
xmit->tail = (xmit->tail + uart->tx_count) & (UART_XMIT_SIZE - 1);
uart->port.icount.tx += uart->tx_count;
uart->tx_count = 0;
uart->tx_done = 1;
#else
#ifdef CONFIG_BF54x
/* Clear TFI bit */
UART_PUT_LSR(uart, TFI);
UART_CLEAR_IER(uart, ETBEI);
#else
ier = UART_GET_IER(uart);
ier &= ~ETBEI;
UART_PUT_IER(uart, ier);
#endif
#endif
}
/*
* port is locked and interrupts are disabled
*/
static void bfin_serial_start_tx(struct uart_port *port)
{
struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
#ifdef CONFIG_SERIAL_BFIN_DMA
if (uart->tx_done)
bfin_serial_dma_tx_chars(uart);
#else
#ifdef CONFIG_BF54x
UART_SET_IER(uart, ETBEI);
#else
unsigned short ier;
ier = UART_GET_IER(uart);
ier |= ETBEI;
UART_PUT_IER(uart, ier);
#endif
bfin_serial_tx_chars(uart);
#endif
}
/*
* Interrupts are enabled
*/
static void bfin_serial_stop_rx(struct uart_port *port)
{
struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
#ifdef CONFIG_KGDB_UART
if (uart->port.line != CONFIG_KGDB_UART_PORT) {
#endif
#ifdef CONFIG_BF54x
UART_CLEAR_IER(uart, ERBFI);
#else
unsigned short ier;
ier = UART_GET_IER(uart);
ier &= ~ERBFI;
UART_PUT_IER(uart, ier);
#endif
#ifdef CONFIG_KGDB_UART
}
#endif
}
/*
* Set the modem control timer to fire immediately.
*/
static void bfin_serial_enable_ms(struct uart_port *port)
{
}
#ifdef CONFIG_KGDB_UART
static int kgdb_entry_state;
void kgdb_put_debug_char(int chr)
{
struct bfin_serial_port *uart;
if (CONFIG_KGDB_UART_PORT<0 || CONFIG_KGDB_UART_PORT>=NR_PORTS)
uart = &bfin_serial_ports[0];
else
uart = &bfin_serial_ports[CONFIG_KGDB_UART_PORT];
while (!(UART_GET_LSR(uart) & THRE)) {
SSYNC();
}
#ifndef CONFIG_BF54x
UART_PUT_LCR(uart, UART_GET_LCR(uart)&(~DLAB));
SSYNC();
#endif
UART_PUT_CHAR(uart, (unsigned char)chr);
SSYNC();
}
int kgdb_get_debug_char(void)
{
struct bfin_serial_port *uart;
unsigned char chr;
if (CONFIG_KGDB_UART_PORT<0 || CONFIG_KGDB_UART_PORT>=NR_PORTS)
uart = &bfin_serial_ports[0];
else
uart = &bfin_serial_ports[CONFIG_KGDB_UART_PORT];
while(!(UART_GET_LSR(uart) & DR)) {
SSYNC();
}
#ifndef CONFIG_BF54x
UART_PUT_LCR(uart, UART_GET_LCR(uart)&(~DLAB));
SSYNC();
#endif
chr = UART_GET_CHAR(uart);
SSYNC();
return chr;
}
#endif
#if ANOMALY_05000230 && defined(CONFIG_SERIAL_BFIN_PIO)
# define UART_GET_ANOMALY_THRESHOLD(uart) ((uart)->anomaly_threshold)
# define UART_SET_ANOMALY_THRESHOLD(uart, v) ((uart)->anomaly_threshold = (v))
#else
# define UART_GET_ANOMALY_THRESHOLD(uart) 0
# define UART_SET_ANOMALY_THRESHOLD(uart, v)
#endif
#ifdef CONFIG_SERIAL_BFIN_PIO
static void bfin_serial_rx_chars(struct bfin_serial_port *uart)
{
struct tty_struct *tty = uart->port.info->tty;
unsigned int status, ch, flg;
static struct timeval anomaly_start = { .tv_sec = 0 };
#ifdef CONFIG_KGDB_UART
struct pt_regs *regs = get_irq_regs();
#endif
status = UART_GET_LSR(uart);
UART_CLEAR_LSR(uart);
ch = UART_GET_CHAR(uart);
uart->port.icount.rx++;
#ifdef CONFIG_KGDB_UART
if (uart->port.line == CONFIG_KGDB_UART_PORT) {
if (uart->port.cons->index == CONFIG_KGDB_UART_PORT && ch == 0x1) { /* Ctrl + A */
kgdb_breakkey_pressed(regs);
return;
} else if (kgdb_entry_state == 0 && ch == '$') {/* connection from KGDB */
kgdb_entry_state = 1;
} else if (kgdb_entry_state == 1 && ch == 'q') {
kgdb_entry_state = 0;
kgdb_breakkey_pressed(regs);
return;
} else if (ch == 0x3) {/* Ctrl + C */
kgdb_entry_state = 0;
kgdb_breakkey_pressed(regs);
return;
} else {
kgdb_entry_state = 0;
}
}
#endif
if (ANOMALY_05000230) {
/* The BF533 (and BF561) family of processors have a nice anomaly
* where they continuously generate characters for a "single" break.
* We have to basically ignore this flood until the "next" valid
* character comes across. Due to the nature of the flood, it is
* not possible to reliably catch bytes that are sent too quickly
* after this break. So application code talking to the Blackfin
* which sends a break signal must allow at least 1.5 character
* times after the end of the break for things to stabilize. This
* timeout was picked as it must absolutely be larger than 1
* character time +/- some percent. So 1.5 sounds good. All other
* Blackfin families operate properly. Woo.
* Note: While Anomaly 05000230 does not directly address this,
* the changes that went in for it also fixed this issue.
* That anomaly was fixed in 0.5+ silicon. I like bunnies.
*/
if (anomaly_start.tv_sec) {
struct timeval curr;
suseconds_t usecs;
if ((~ch & (~ch + 1)) & 0xff)
goto known_good_char;
do_gettimeofday(&curr);
if (curr.tv_sec - anomaly_start.tv_sec > 1)
goto known_good_char;
usecs = 0;
if (curr.tv_sec != anomaly_start.tv_sec)
usecs += USEC_PER_SEC;
usecs += curr.tv_usec - anomaly_start.tv_usec;
if (usecs > UART_GET_ANOMALY_THRESHOLD(uart))
goto known_good_char;
if (ch)
anomaly_start.tv_sec = 0;
else
anomaly_start = curr;
return;
known_good_char:
anomaly_start.tv_sec = 0;
}
}
if (status & BI) {
if (ANOMALY_05000230)
if (bfin_revid() < 5)
do_gettimeofday(&anomaly_start);
uart->port.icount.brk++;
if (uart_handle_break(&uart->port))
goto ignore_char;
status &= ~(PE | FE);
}
if (status & PE)
uart->port.icount.parity++;
if (status & OE)
uart->port.icount.overrun++;
if (status & FE)
uart->port.icount.frame++;
status &= uart->port.read_status_mask;
if (status & BI)
flg = TTY_BREAK;
else if (status & PE)
flg = TTY_PARITY;
else if (status & FE)
flg = TTY_FRAME;
else
flg = TTY_NORMAL;
if (uart_handle_sysrq_char(&uart->port, ch))
goto ignore_char;
uart_insert_char(&uart->port, status, OE, ch, flg);
ignore_char:
tty_flip_buffer_push(tty);
}
static void bfin_serial_tx_chars(struct bfin_serial_port *uart)
{
struct circ_buf *xmit = &uart->port.info->xmit;
if (uart->port.x_char) {
UART_PUT_CHAR(uart, uart->port.x_char);
uart->port.icount.tx++;
uart->port.x_char = 0;
}
/*
* Check the modem control lines before
* transmitting anything.
*/
bfin_serial_mctrl_check(uart);
if (uart_circ_empty(xmit) || uart_tx_stopped(&uart->port)) {
bfin_serial_stop_tx(&uart->port);
return;
}
while ((UART_GET_LSR(uart) & THRE) && xmit->tail != xmit->head) {
UART_PUT_CHAR(uart, xmit->buf[xmit->tail]);
xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
uart->port.icount.tx++;
SSYNC();
}
if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
uart_write_wakeup(&uart->port);
if (uart_circ_empty(xmit))
bfin_serial_stop_tx(&uart->port);
}
static irqreturn_t bfin_serial_rx_int(int irq, void *dev_id)
{
struct bfin_serial_port *uart = dev_id;
spin_lock(&uart->port.lock);
while (UART_GET_LSR(uart) & DR)
bfin_serial_rx_chars(uart);
spin_unlock(&uart->port.lock);
return IRQ_HANDLED;
}
static irqreturn_t bfin_serial_tx_int(int irq, void *dev_id)
{
struct bfin_serial_port *uart = dev_id;
spin_lock(&uart->port.lock);
if (UART_GET_LSR(uart) & THRE)
bfin_serial_tx_chars(uart);
spin_unlock(&uart->port.lock);
return IRQ_HANDLED;
}
#endif
#ifdef CONFIG_SERIAL_BFIN_CTSRTS
static void bfin_serial_do_work(struct work_struct *work)
{
struct bfin_serial_port *uart = container_of(work, struct bfin_serial_port, cts_workqueue);
bfin_serial_mctrl_check(uart);
}
#endif
#ifdef CONFIG_SERIAL_BFIN_DMA
static void bfin_serial_dma_tx_chars(struct bfin_serial_port *uart)
{
struct circ_buf *xmit = &uart->port.info->xmit;
unsigned short ier;
uart->tx_done = 0;
if (uart_circ_empty(xmit) || uart_tx_stopped(&uart->port)) {
uart->tx_count = 0;
uart->tx_done = 1;
return;
}
if (uart->port.x_char) {
UART_PUT_CHAR(uart, uart->port.x_char);
uart->port.icount.tx++;
uart->port.x_char = 0;
}
/*
* Check the modem control lines before
* transmitting anything.
*/
bfin_serial_mctrl_check(uart);
uart->tx_count = CIRC_CNT(xmit->head, xmit->tail, UART_XMIT_SIZE);
if (uart->tx_count > (UART_XMIT_SIZE - xmit->tail))
uart->tx_count = UART_XMIT_SIZE - xmit->tail;
blackfin_dcache_flush_range((unsigned long)(xmit->buf+xmit->tail),
(unsigned long)(xmit->buf+xmit->tail+uart->tx_count));
set_dma_config(uart->tx_dma_channel,
set_bfin_dma_config(DIR_READ, DMA_FLOW_STOP,
INTR_ON_BUF,
DIMENSION_LINEAR,
DATA_SIZE_8,
DMA_SYNC_RESTART));
set_dma_start_addr(uart->tx_dma_channel, (unsigned long)(xmit->buf+xmit->tail));
set_dma_x_count(uart->tx_dma_channel, uart->tx_count);
set_dma_x_modify(uart->tx_dma_channel, 1);
enable_dma(uart->tx_dma_channel);
#ifdef CONFIG_BF54x
UART_SET_IER(uart, ETBEI);
#else
ier = UART_GET_IER(uart);
ier |= ETBEI;
UART_PUT_IER(uart, ier);
#endif
}
static void bfin_serial_dma_rx_chars(struct bfin_serial_port *uart)
{
struct tty_struct *tty = uart->port.info->tty;
int i, flg, status;
status = UART_GET_LSR(uart);
UART_CLEAR_LSR(uart);
uart->port.icount.rx +=
CIRC_CNT(uart->rx_dma_buf.head, uart->rx_dma_buf.tail,
UART_XMIT_SIZE);
if (status & BI) {
uart->port.icount.brk++;
if (uart_handle_break(&uart->port))
goto dma_ignore_char;
status &= ~(PE | FE);
}
if (status & PE)
uart->port.icount.parity++;
if (status & OE)
uart->port.icount.overrun++;
if (status & FE)
uart->port.icount.frame++;
status &= uart->port.read_status_mask;
if (status & BI)
flg = TTY_BREAK;
else if (status & PE)
flg = TTY_PARITY;
else if (status & FE)
flg = TTY_FRAME;
else
flg = TTY_NORMAL;
for (i = uart->rx_dma_buf.tail; i != uart->rx_dma_buf.head; i++) {
if (i >= UART_XMIT_SIZE)
i = 0;
if (!uart_handle_sysrq_char(&uart->port, uart->rx_dma_buf.buf[i]))
uart_insert_char(&uart->port, status, OE,
uart->rx_dma_buf.buf[i], flg);
}
dma_ignore_char:
tty_flip_buffer_push(tty);
}
void bfin_serial_rx_dma_timeout(struct bfin_serial_port *uart)
{
int x_pos, pos;
uart->rx_dma_nrows = get_dma_curr_ycount(uart->rx_dma_channel);
x_pos = get_dma_curr_xcount(uart->rx_dma_channel);
uart->rx_dma_nrows = DMA_RX_YCOUNT - uart->rx_dma_nrows;
if (uart->rx_dma_nrows == DMA_RX_YCOUNT)
uart->rx_dma_nrows = 0;
x_pos = DMA_RX_XCOUNT - x_pos;
if (x_pos == DMA_RX_XCOUNT)
x_pos = 0;
pos = uart->rx_dma_nrows * DMA_RX_XCOUNT + x_pos;
if (pos != uart->rx_dma_buf.tail) {
uart->rx_dma_buf.head = pos;
bfin_serial_dma_rx_chars(uart);
uart->rx_dma_buf.tail = uart->rx_dma_buf.head;
}
uart->rx_dma_timer.expires = jiffies + DMA_RX_FLUSH_JIFFIES;
add_timer(&(uart->rx_dma_timer));
}
static irqreturn_t bfin_serial_dma_tx_int(int irq, void *dev_id)
{
struct bfin_serial_port *uart = dev_id;
struct circ_buf *xmit = &uart->port.info->xmit;
unsigned short ier;
spin_lock(&uart->port.lock);
if (!(get_dma_curr_irqstat(uart->tx_dma_channel)&DMA_RUN)) {
disable_dma(uart->tx_dma_channel);
clear_dma_irqstat(uart->tx_dma_channel);
#ifdef CONFIG_BF54x
UART_CLEAR_IER(uart, ETBEI);
#else
ier = UART_GET_IER(uart);
ier &= ~ETBEI;
UART_PUT_IER(uart, ier);
#endif
xmit->tail = (xmit->tail + uart->tx_count) & (UART_XMIT_SIZE - 1);
uart->port.icount.tx += uart->tx_count;
if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
uart_write_wakeup(&uart->port);
bfin_serial_dma_tx_chars(uart);
}
spin_unlock(&uart->port.lock);
return IRQ_HANDLED;
}
static irqreturn_t bfin_serial_dma_rx_int(int irq, void *dev_id)
{
struct bfin_serial_port *uart = dev_id;
unsigned short irqstat;
spin_lock(&uart->port.lock);
irqstat = get_dma_curr_irqstat(uart->rx_dma_channel);
clear_dma_irqstat(uart->rx_dma_channel);
spin_unlock(&uart->port.lock);
del_timer(&(uart->rx_dma_timer));
uart->rx_dma_timer.expires = jiffies;
add_timer(&(uart->rx_dma_timer));
return IRQ_HANDLED;
}
#endif
/*
* Return TIOCSER_TEMT when transmitter is not busy.
*/
static unsigned int bfin_serial_tx_empty(struct uart_port *port)
{
struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
unsigned short lsr;
lsr = UART_GET_LSR(uart);
if (lsr & TEMT)
return TIOCSER_TEMT;
else
return 0;
}
static unsigned int bfin_serial_get_mctrl(struct uart_port *port)
{
#ifdef CONFIG_SERIAL_BFIN_CTSRTS
struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
if (uart->cts_pin < 0)
return TIOCM_CTS | TIOCM_DSR | TIOCM_CAR;
# ifdef BF54x
if (UART_GET_MSR(uart) & CTS)
# else
if (gpio_get_value(uart->cts_pin))
# endif
return TIOCM_DSR | TIOCM_CAR;
else
#endif
return TIOCM_CTS | TIOCM_DSR | TIOCM_CAR;
}
static void bfin_serial_set_mctrl(struct uart_port *port, unsigned int mctrl)
{
#ifdef CONFIG_SERIAL_BFIN_CTSRTS
struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
if (uart->rts_pin < 0)
return;
if (mctrl & TIOCM_RTS)
# ifdef BF54x
UART_PUT_MCR(uart, UART_GET_MCR(uart) & ~MRTS);
# else
gpio_set_value(uart->rts_pin, 0);
# endif
else
# ifdef BF54x
UART_PUT_MCR(uart, UART_GET_MCR(uart) | MRTS);
# else
gpio_set_value(uart->rts_pin, 1);
# endif
#endif
}
/*
* Handle any change of modem status signal since we were last called.
*/
static void bfin_serial_mctrl_check(struct bfin_serial_port *uart)
{
#ifdef CONFIG_SERIAL_BFIN_CTSRTS
unsigned int status;
struct uart_info *info = uart->port.info;
struct tty_struct *tty = info->tty;
status = bfin_serial_get_mctrl(&uart->port);
uart_handle_cts_change(&uart->port, status & TIOCM_CTS);
if (!(status & TIOCM_CTS)) {
tty->hw_stopped = 1;
schedule_work(&uart->cts_workqueue);
} else {
tty->hw_stopped = 0;
}
#endif
}
/*
* Interrupts are always disabled.
*/
static void bfin_serial_break_ctl(struct uart_port *port, int break_state)
{
struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
u16 lcr = UART_GET_LCR(uart);
if (break_state)
lcr |= SB;
else
lcr &= ~SB;
UART_PUT_LCR(uart, lcr);
SSYNC();
}
static int bfin_serial_startup(struct uart_port *port)
{
struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
#ifdef CONFIG_SERIAL_BFIN_DMA
dma_addr_t dma_handle;
if (request_dma(uart->rx_dma_channel, "BFIN_UART_RX") < 0) {
printk(KERN_NOTICE "Unable to attach Blackfin UART RX DMA channel\n");
return -EBUSY;
}
if (request_dma(uart->tx_dma_channel, "BFIN_UART_TX") < 0) {
printk(KERN_NOTICE "Unable to attach Blackfin UART TX DMA channel\n");
free_dma(uart->rx_dma_channel);
return -EBUSY;
}
set_dma_callback(uart->rx_dma_channel, bfin_serial_dma_rx_int, uart);
set_dma_callback(uart->tx_dma_channel, bfin_serial_dma_tx_int, uart);
uart->rx_dma_buf.buf = (unsigned char *)dma_alloc_coherent(NULL, PAGE_SIZE, &dma_handle, GFP_DMA);
uart->rx_dma_buf.head = 0;
uart->rx_dma_buf.tail = 0;
uart->rx_dma_nrows = 0;
set_dma_config(uart->rx_dma_channel,
set_bfin_dma_config(DIR_WRITE, DMA_FLOW_AUTO,
INTR_ON_ROW, DIMENSION_2D,
DATA_SIZE_8,
DMA_SYNC_RESTART));
set_dma_x_count(uart->rx_dma_channel, DMA_RX_XCOUNT);
set_dma_x_modify(uart->rx_dma_channel, 1);
set_dma_y_count(uart->rx_dma_channel, DMA_RX_YCOUNT);
set_dma_y_modify(uart->rx_dma_channel, 1);
set_dma_start_addr(uart->rx_dma_channel, (unsigned long)uart->rx_dma_buf.buf);
enable_dma(uart->rx_dma_channel);
uart->rx_dma_timer.data = (unsigned long)(uart);
uart->rx_dma_timer.function = (void *)bfin_serial_rx_dma_timeout;
uart->rx_dma_timer.expires = jiffies + DMA_RX_FLUSH_JIFFIES;
add_timer(&(uart->rx_dma_timer));
#else
if (request_irq(uart->port.irq, bfin_serial_rx_int, IRQF_DISABLED,
"BFIN_UART_RX", uart)) {
# ifdef CONFIG_KGDB_UART
if (uart->port.line != CONFIG_KGDB_UART_PORT) {
# endif
printk(KERN_NOTICE "Unable to attach BlackFin UART RX interrupt\n");
return -EBUSY;
# ifdef CONFIG_KGDB_UART
}
# endif
}
if (request_irq
(uart->port.irq+1, bfin_serial_tx_int, IRQF_DISABLED,
"BFIN_UART_TX", uart)) {
printk(KERN_NOTICE "Unable to attach BlackFin UART TX interrupt\n");
free_irq(uart->port.irq, uart);
return -EBUSY;
}
#endif
#ifdef CONFIG_BF54x
UART_SET_IER(uart, ERBFI);
#else
UART_PUT_IER(uart, UART_GET_IER(uart) | ERBFI);
#endif
return 0;
}
static void bfin_serial_shutdown(struct uart_port *port)
{
struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
#ifdef CONFIG_SERIAL_BFIN_DMA
disable_dma(uart->tx_dma_channel);
free_dma(uart->tx_dma_channel);
disable_dma(uart->rx_dma_channel);
free_dma(uart->rx_dma_channel);
del_timer(&(uart->rx_dma_timer));
dma_free_coherent(NULL, PAGE_SIZE, uart->rx_dma_buf.buf, 0);
#else
#ifdef CONFIG_KGDB_UART
if (uart->port.line != CONFIG_KGDB_UART_PORT)
#endif
free_irq(uart->port.irq, uart);
free_irq(uart->port.irq+1, uart);
#endif
}
static void
bfin_serial_set_termios(struct uart_port *port, struct ktermios *termios,
struct ktermios *old)
{
struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
unsigned long flags;
unsigned int baud, quot;
unsigned short val, ier, lcr = 0;
switch (termios->c_cflag & CSIZE) {
case CS8:
lcr = WLS(8);
break;
case CS7:
lcr = WLS(7);
break;
case CS6:
lcr = WLS(6);
break;
case CS5:
lcr = WLS(5);
break;
default:
printk(KERN_ERR "%s: word lengh not supported\n",
__FUNCTION__);
}
if (termios->c_cflag & CSTOPB)
lcr |= STB;
if (termios->c_cflag & PARENB)
lcr |= PEN;
if (!(termios->c_cflag & PARODD))
lcr |= EPS;
if (termios->c_cflag & CMSPAR)
lcr |= STP;
port->read_status_mask = OE;
if (termios->c_iflag & INPCK)
port->read_status_mask |= (FE | PE);
if (termios->c_iflag & (BRKINT | PARMRK))
port->read_status_mask |= BI;
/*
* Characters to ignore
*/
port->ignore_status_mask = 0;
if (termios->c_iflag & IGNPAR)
port->ignore_status_mask |= FE | PE;
if (termios->c_iflag & IGNBRK) {
port->ignore_status_mask |= BI;
/*
* If we're ignoring parity and break indicators,
* ignore overruns too (for real raw support).
*/
if (termios->c_iflag & IGNPAR)
port->ignore_status_mask |= OE;
}
baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16);
quot = uart_get_divisor(port, baud);
spin_lock_irqsave(&uart->port.lock, flags);
UART_SET_ANOMALY_THRESHOLD(uart, USEC_PER_SEC / baud * 15);
/* Disable UART */
ier = UART_GET_IER(uart);
#ifdef CONFIG_BF54x
UART_CLEAR_IER(uart, 0xF);
#else
UART_PUT_IER(uart, 0);
#endif
#ifndef CONFIG_BF54x
/* Set DLAB in LCR to Access DLL and DLH */
val = UART_GET_LCR(uart);
val |= DLAB;
UART_PUT_LCR(uart, val);
SSYNC();
#endif
UART_PUT_DLL(uart, quot & 0xFF);
SSYNC();
UART_PUT_DLH(uart, (quot >> 8) & 0xFF);
SSYNC();
#ifndef CONFIG_BF54x
/* Clear DLAB in LCR to Access THR RBR IER */
val = UART_GET_LCR(uart);
val &= ~DLAB;
UART_PUT_LCR(uart, val);
SSYNC();
#endif
UART_PUT_LCR(uart, lcr);
/* Enable UART */
#ifdef CONFIG_BF54x
UART_SET_IER(uart, ier);
#else
UART_PUT_IER(uart, ier);
#endif
val = UART_GET_GCTL(uart);
val |= UCEN;
UART_PUT_GCTL(uart, val);
spin_unlock_irqrestore(&uart->port.lock, flags);
}
static const char *bfin_serial_type(struct uart_port *port)
{
struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
return uart->port.type == PORT_BFIN ? "BFIN-UART" : NULL;
}
/*
* Release the memory region(s) being used by 'port'.
*/
static void bfin_serial_release_port(struct uart_port *port)
{
}
/*
* Request the memory region(s) being used by 'port'.
*/
static int bfin_serial_request_port(struct uart_port *port)
{
return 0;
}
/*
* Configure/autoconfigure the port.
*/
static void bfin_serial_config_port(struct uart_port *port, int flags)
{
struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
if (flags & UART_CONFIG_TYPE &&
bfin_serial_request_port(&uart->port) == 0)
uart->port.type = PORT_BFIN;
}
/*
* Verify the new serial_struct (for TIOCSSERIAL).
* The only change we allow are to the flags and type, and
* even then only between PORT_BFIN and PORT_UNKNOWN
*/
static int
bfin_serial_verify_port(struct uart_port *port, struct serial_struct *ser)
{
return 0;
}
/*
* Enable the IrDA function if tty->ldisc.num is N_IRDA.
* In other cases, disable IrDA function.
*/
static void bfin_set_ldisc(struct tty_struct *tty)
{
int line = tty->index;
unsigned short val;
if (line >= tty->driver->num)
return;
switch (tty->ldisc.num) {
case N_IRDA:
val = UART_GET_GCTL(&bfin_serial_ports[line]);
val |= (IREN | RPOLC);
UART_PUT_GCTL(&bfin_serial_ports[line], val);
break;
default:
val = UART_GET_GCTL(&bfin_serial_ports[line]);
val &= ~(IREN | RPOLC);
UART_PUT_GCTL(&bfin_serial_ports[line], val);
}
}
static struct uart_ops bfin_serial_pops = {
.tx_empty = bfin_serial_tx_empty,
.set_mctrl = bfin_serial_set_mctrl,
.get_mctrl = bfin_serial_get_mctrl,
.stop_tx = bfin_serial_stop_tx,
.start_tx = bfin_serial_start_tx,
.stop_rx = bfin_serial_stop_rx,
.enable_ms = bfin_serial_enable_ms,
.break_ctl = bfin_serial_break_ctl,
.startup = bfin_serial_startup,
.shutdown = bfin_serial_shutdown,
.set_termios = bfin_serial_set_termios,
.type = bfin_serial_type,
.release_port = bfin_serial_release_port,
.request_port = bfin_serial_request_port,
.config_port = bfin_serial_config_port,
.verify_port = bfin_serial_verify_port,
};
static void __init bfin_serial_init_ports(void)
{
static int first = 1;
int i;
if (!first)
return;
first = 0;
for (i = 0; i < nr_ports; i++) {
bfin_serial_ports[i].port.uartclk = get_sclk();
bfin_serial_ports[i].port.ops = &bfin_serial_pops;
bfin_serial_ports[i].port.line = i;
bfin_serial_ports[i].port.iotype = UPIO_MEM;
bfin_serial_ports[i].port.membase =
(void __iomem *)bfin_serial_resource[i].uart_base_addr;
bfin_serial_ports[i].port.mapbase =
bfin_serial_resource[i].uart_base_addr;
bfin_serial_ports[i].port.irq =
bfin_serial_resource[i].uart_irq;
bfin_serial_ports[i].port.flags = UPF_BOOT_AUTOCONF;
#ifdef CONFIG_SERIAL_BFIN_DMA
bfin_serial_ports[i].tx_done = 1;
bfin_serial_ports[i].tx_count = 0;
bfin_serial_ports[i].tx_dma_channel =
bfin_serial_resource[i].uart_tx_dma_channel;
bfin_serial_ports[i].rx_dma_channel =
bfin_serial_resource[i].uart_rx_dma_channel;
init_timer(&(bfin_serial_ports[i].rx_dma_timer));
#endif
#ifdef CONFIG_SERIAL_BFIN_CTSRTS
INIT_WORK(&bfin_serial_ports[i].cts_workqueue, bfin_serial_do_work);
bfin_serial_ports[i].cts_pin =
bfin_serial_resource[i].uart_cts_pin;
bfin_serial_ports[i].rts_pin =
bfin_serial_resource[i].uart_rts_pin;
#endif
bfin_serial_hw_init(&bfin_serial_ports[i]);
}
}
#ifdef CONFIG_SERIAL_BFIN_CONSOLE
/*
* If the port was already initialised (eg, by a boot loader),
* try to determine the current setup.
*/
static void __init
bfin_serial_console_get_options(struct bfin_serial_port *uart, int *baud,
int *parity, int *bits)
{
unsigned short status;
status = UART_GET_IER(uart) & (ERBFI | ETBEI);
if (status == (ERBFI | ETBEI)) {
/* ok, the port was enabled */
unsigned short lcr, val;
unsigned short dlh, dll;
lcr = UART_GET_LCR(uart);
*parity = 'n';
if (lcr & PEN) {
if (lcr & EPS)
*parity = 'e';
else
*parity = 'o';
}
switch (lcr & 0x03) {
case 0: *bits = 5; break;
case 1: *bits = 6; break;
case 2: *bits = 7; break;
case 3: *bits = 8; break;
}
#ifndef CONFIG_BF54x
/* Set DLAB in LCR to Access DLL and DLH */
val = UART_GET_LCR(uart);
val |= DLAB;
UART_PUT_LCR(uart, val);
#endif
dll = UART_GET_DLL(uart);
dlh = UART_GET_DLH(uart);
#ifndef CONFIG_BF54x
/* Clear DLAB in LCR to Access THR RBR IER */
val = UART_GET_LCR(uart);
val &= ~DLAB;
UART_PUT_LCR(uart, val);
#endif
*baud = get_sclk() / (16*(dll | dlh << 8));
}
pr_debug("%s:baud = %d, parity = %c, bits= %d\n", __FUNCTION__, *baud, *parity, *bits);
}
#endif
#if defined(CONFIG_SERIAL_BFIN_CONSOLE) || defined(CONFIG_EARLY_PRINTK)
static struct uart_driver bfin_serial_reg;
static int __init
bfin_serial_console_setup(struct console *co, char *options)
{
struct bfin_serial_port *uart;
# ifdef CONFIG_SERIAL_BFIN_CONSOLE
int baud = 57600;
int bits = 8;
int parity = 'n';
# ifdef CONFIG_SERIAL_BFIN_CTSRTS
int flow = 'r';
# else
int flow = 'n';
# endif
# endif
/*
* Check whether an invalid uart number has been specified, and
* if so, search for the first available port that does have
* console support.
*/
if (co->index == -1 || co->index >= nr_ports)
co->index = 0;
uart = &bfin_serial_ports[co->index];
# ifdef CONFIG_SERIAL_BFIN_CONSOLE
if (options)
uart_parse_options(options, &baud, &parity, &bits, &flow);
else
bfin_serial_console_get_options(uart, &baud, &parity, &bits);
return uart_set_options(&uart->port, co, baud, parity, bits, flow);
# else
return 0;
# endif
}
#endif /* defined (CONFIG_SERIAL_BFIN_CONSOLE) ||
defined (CONFIG_EARLY_PRINTK) */
#ifdef CONFIG_SERIAL_BFIN_CONSOLE
static void bfin_serial_console_putchar(struct uart_port *port, int ch)
{
struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
while (!(UART_GET_LSR(uart) & THRE))
barrier();
UART_PUT_CHAR(uart, ch);
SSYNC();
}
/*
* Interrupts are disabled on entering
*/
static void
bfin_serial_console_write(struct console *co, const char *s, unsigned int count)
{
struct bfin_serial_port *uart = &bfin_serial_ports[co->index];
int flags = 0;
spin_lock_irqsave(&uart->port.lock, flags);
uart_console_write(&uart->port, s, count, bfin_serial_console_putchar);
spin_unlock_irqrestore(&uart->port.lock, flags);
}
static struct console bfin_serial_console = {
.name = BFIN_SERIAL_NAME,
.write = bfin_serial_console_write,
.device = uart_console_device,
.setup = bfin_serial_console_setup,
.flags = CON_PRINTBUFFER,
.index = -1,
.data = &bfin_serial_reg,
};
static int __init bfin_serial_rs_console_init(void)
{
bfin_serial_init_ports();
register_console(&bfin_serial_console);
#ifdef CONFIG_KGDB_UART
kgdb_entry_state = 0;
init_kgdb_uart();
#endif
return 0;
}
console_initcall(bfin_serial_rs_console_init);
#define BFIN_SERIAL_CONSOLE &bfin_serial_console
#else
#define BFIN_SERIAL_CONSOLE NULL
#endif /* CONFIG_SERIAL_BFIN_CONSOLE */
#ifdef CONFIG_EARLY_PRINTK
static __init void early_serial_putc(struct uart_port *port, int ch)
{
unsigned timeout = 0xffff;
struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
while ((!(UART_GET_LSR(uart) & THRE)) && --timeout)
cpu_relax();
UART_PUT_CHAR(uart, ch);
}
static __init void early_serial_write(struct console *con, const char *s,
unsigned int n)
{
struct bfin_serial_port *uart = &bfin_serial_ports[con->index];
unsigned int i;
for (i = 0; i < n; i++, s++) {
if (*s == '\n')
early_serial_putc(&uart->port, '\r');
early_serial_putc(&uart->port, *s);
}
}
static struct __init console bfin_early_serial_console = {
.name = "early_BFuart",
.write = early_serial_write,
.device = uart_console_device,
.flags = CON_PRINTBUFFER,
.setup = bfin_serial_console_setup,
.index = -1,
.data = &bfin_serial_reg,
};
struct console __init *bfin_earlyserial_init(unsigned int port,
unsigned int cflag)
{
struct bfin_serial_port *uart;
struct ktermios t;
if (port == -1 || port >= nr_ports)
port = 0;
bfin_serial_init_ports();
bfin_early_serial_console.index = port;
uart = &bfin_serial_ports[port];
t.c_cflag = cflag;
t.c_iflag = 0;
t.c_oflag = 0;
t.c_lflag = ICANON;
t.c_line = port;
bfin_serial_set_termios(&uart->port, &t, &t);
return &bfin_early_serial_console;
}
#endif /* CONFIG_SERIAL_BFIN_CONSOLE */
static struct uart_driver bfin_serial_reg = {
.owner = THIS_MODULE,
.driver_name = "bfin-uart",
.dev_name = BFIN_SERIAL_NAME,
.major = BFIN_SERIAL_MAJOR,
.minor = BFIN_SERIAL_MINOR,
.nr = NR_PORTS,
.cons = BFIN_SERIAL_CONSOLE,
};
static int bfin_serial_suspend(struct platform_device *dev, pm_message_t state)
{
struct bfin_serial_port *uart = platform_get_drvdata(dev);
if (uart)
uart_suspend_port(&bfin_serial_reg, &uart->port);
return 0;
}
static int bfin_serial_resume(struct platform_device *dev)
{
struct bfin_serial_port *uart = platform_get_drvdata(dev);
if (uart)
uart_resume_port(&bfin_serial_reg, &uart->port);
return 0;
}
static int bfin_serial_probe(struct platform_device *dev)
{
struct resource *res = dev->resource;
int i;
for (i = 0; i < dev->num_resources; i++, res++)
if (res->flags & IORESOURCE_MEM)
break;
if (i < dev->num_resources) {
for (i = 0; i < nr_ports; i++, res++) {
if (bfin_serial_ports[i].port.mapbase != res->start)
continue;
bfin_serial_ports[i].port.dev = &dev->dev;
uart_add_one_port(&bfin_serial_reg, &bfin_serial_ports[i].port);
platform_set_drvdata(dev, &bfin_serial_ports[i]);
}
}
return 0;
}
static int bfin_serial_remove(struct platform_device *pdev)
{
struct bfin_serial_port *uart = platform_get_drvdata(pdev);
#ifdef CONFIG_SERIAL_BFIN_CTSRTS
gpio_free(uart->cts_pin);
gpio_free(uart->rts_pin);
#endif
platform_set_drvdata(pdev, NULL);
if (uart)
uart_remove_one_port(&bfin_serial_reg, &uart->port);
return 0;
}
static struct platform_driver bfin_serial_driver = {
.probe = bfin_serial_probe,
.remove = bfin_serial_remove,
.suspend = bfin_serial_suspend,
.resume = bfin_serial_resume,
.driver = {
.name = "bfin-uart",
.owner = THIS_MODULE,
},
};
static int __init bfin_serial_init(void)
{
int ret;
#ifdef CONFIG_KGDB_UART
struct bfin_serial_port *uart = &bfin_serial_ports[CONFIG_KGDB_UART_PORT];
struct ktermios t;
#endif
pr_info("Serial: Blackfin serial driver\n");
bfin_serial_init_ports();
ret = uart_register_driver(&bfin_serial_reg);
if (ret == 0) {
bfin_serial_reg.tty_driver->set_ldisc = bfin_set_ldisc;
ret = platform_driver_register(&bfin_serial_driver);
if (ret) {
pr_debug("uart register failed\n");
uart_unregister_driver(&bfin_serial_reg);
}
}
#ifdef CONFIG_KGDB_UART
if (uart->port.cons->index != CONFIG_KGDB_UART_PORT) {
request_irq(uart->port.irq, bfin_serial_rx_int,
IRQF_DISABLED, "BFIN_UART_RX", uart);
pr_info("Request irq for kgdb uart port\n");
#ifdef CONFIG_BF54x
UART_SET_IER(uart, ERBFI);
#else
UART_PUT_IER(uart, UART_GET_IER(uart) | ERBFI);
#endif
SSYNC();
t.c_cflag = CS8|B57600;
t.c_iflag = 0;
t.c_oflag = 0;
t.c_lflag = ICANON;
t.c_line = CONFIG_KGDB_UART_PORT;
bfin_serial_set_termios(&uart->port, &t, &t);
}
#endif
return ret;
}
static void __exit bfin_serial_exit(void)
{
platform_driver_unregister(&bfin_serial_driver);
uart_unregister_driver(&bfin_serial_reg);
}
module_init(bfin_serial_init);
module_exit(bfin_serial_exit);
MODULE_AUTHOR("Aubrey.Li <aubrey.li@analog.com>");
MODULE_DESCRIPTION("Blackfin generic serial port driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS_CHARDEV_MAJOR(BFIN_SERIAL_MAJOR);
MODULE_ALIAS("platform:bfin-uart");
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